The invention disclosed herein generally relates to matrices comprising polymers and methods for preparing them.

A polymer composition for producing gel extruded articles is described. The polymer composition contains at least three different polyethylene polymers, namely a lower molecular weight polyethylene polymer, a mid-range molecular weight polyethylene polymer, and a high molecular weight polyethylene polymer. Combining the different polyethylene polymers in different ratios can optimize not only mechanical properties but improve processing.

A method of removing chemical contaminants from a composition comprising an active, a solvent, and a contaminant can include providing an initial feed supply, wherein the initial feed supply comprises the active, the solvent, and the contaminant, wherein the contaminant can include 1,4 dioxane, dimethyl dioxane, or a combination thereof; including filtering the initial feed stock through a nanofilter.

A polymer composition for producing gel extruded articles is described. The polymer composition contains at least three different polyethylene polymers, namely a lower molecular weight polyethylene polymer, a mid-range molecular weight polyethylene polymer, and a high molecular weight polyethylene polymer. Combining the different polyethylene polymers in different ratios can optimize not only mechanical properties but improve processing.

A substrate for a composite membrane includes a microporous polyolefin membrane for carrying a hydrophilic resin compound within the pores of the microporous membrane wherein: the average pore diameter is 1 nm to 50 nm; the porosity is 50% to 78%; the membrane thickness is 1 m to 12 m; and, when a mixed solution of ethanol and water (volume ratio 1/2) is dripped onto a surface of the microporous polyolefin membrane which has not undergone hydrophilization treatment, the contact angle 1 between the droplet and the surface is 0 to 90 degrees 1 second after the dripping, and the contact angle 2 between the droplet and the surface is 0 to 70 degrees 10 minutes after the dripping, and the rate of change of the contact angle ((12)/1100) is 10 to 50%.